Vitamin D, Sun exposure, Cancer

July 29 2016

Vitamin D, Sun exposure, Cancer

This month, I’m sharing what I think is a really important study that was recently published about the link between Vitamin D and cancer.

Here are my take home points:

Multiple PAST epidemiologic studies have suggested a link between inadequate/low vitamin D levels and increased risk of cancers including colon cancer, prostate cancer and breast cancer.

According the U.S. Endocrine society, Vitamin D blood levels lower than 30 ng/ml are considered inadequate. In the U.S., about 70% of the population has vitamin D levels below this. The global average is about 20 ng/ml, which is considered deficient.

In this new published study, the goal was to determine the link between Vitamin D levels and the risk of non-skin cancers in women ages 55 years and older.

To determine the above, two research studies were analyzed- the first study was a randomized controlled trial from Nebraska of over 1,000 women with an average vitamin D blood level of 30 ng/ml. The second study was an international trial looking at more than 1,000 people from over 50 countries; in this trial, the average Vitamin D blood level was 48 ng/ml.

The occurrence of non-skin cancers in the above groups was evaluated over many years and the results showed a lower incidence of cancer with higher Vitamin D levels; women with Vitamin D levels of 40 ng/ml had a 67% LOWER risk of cancer than women whose levels were <20 ng/ml.

Bottom Line

This study offers further compelling evidence about the important link between Vitamin D inadequacy and cancer, showing a substantial reduction of invasive cancer incidence with higher levels (>/= 40ng/ml) of Vitamin D! The best way to know if you’re getting enough Vitamin D is get the blood test that measures your Vitamin D3 levels. If low, I strongly recommend healthy sun exposure and if needed, a Vitamin D3 supplement.

Some personal thoughts on the study

As with a plethora of other studies, while this above study supports the stance of Vitamin D as a “super” supplement, it shows an association of higher vitamin D with less disease but it does not prove higher vitamin D levels as a CAUSE for less disease.

That being said, there have been many randomized control trials that do show Vitamin D3 supplementation to be effective in prolonging one’s lifespan! I am usually not a fan of supplements because I believe in getting one’s minerals and vitamins from their true (usually whole food) sources. However, Vitamin D is an exception to this. For one thing, Vitamin D is not a vitamin but a hormone that is synthesized by our skin as a result of sun exposure. For those patients/clients of mine with high skin cancer risks, Vitamin D3 supplementation I believe is a better option than prolonged sun exposure. Secondly, for a lot of the population, even a healthy amount of sun exposure is not feasible in their current lives, given indoor desk jobs and/or living inNorthern climates with a significant winter. There are also cultural mores for many that motivate many to AVOID the sun, that have nothing to do with fear of cancer.

The third reason I am not against Vitamin D3 supplementation and often recommend it is that while the majority of research around the benefits of Vitamin D show a LINK but not a CAUSAL relationship, the literature is still quite compelling. I can attest that in my clinical experience, I have witnessed improvements in people’s overall well being and in specific elements including mood, blood sugar control, and energy levels, when low levels of Vitamin D were repleted. It is true that this is just one physician’s observation and that not all variables were controlled in my patients’ cases, but given the very high tolerability of Vitamin D and its relative cheap price, I have no problem checking people’s Vitamin D3 levels especially in the cases of persistent ill health. If it is low, and it often is (see the statistic about the percentage of Vitamin D3 inadequacy in the above section), I recommend a healthy amount of sun exposure (and this is individualized to each person) and if needed, also a Vitamin D3 supplement.